Renin inhibitors are expected as a medicine for the prevention and/or treatment of diseases such as hypertension, heart failure, diabetic nephropathy and the like, and 3,4-substituted piperidine derivatives are disclosed for example (Patent Literature 1). But a morpholine derivative is not described in the literature.
Also WO 2008/153182 discloses some morpholine derivatives but they are compounds having a formula I of the present invention wherein R is a hydrogen atom (Patent Literature 2).